This invention relates to a drive motor which can be perfectly stopped just on interruption of electricity and also relates to a coin feeding device which can be rotatable in reverse direction with such a drive motor.
Conventionally, a drive motor of the type described comprises, as illustrated in FIGS. 4 and 5, a motor body 5, a transmission 6, and a motor shaft 11. On being applied to a coin feeding device, the motor body 5 drives the coin feeding device by means of the motor shaft which is rotatable in counterclockwise direction through the transmission 6. Such drive motor is disclosed in, for example, Japanese Patent Examined Publication No. 55-48634.
A coin feeding device comprises a coin hopper 1 where a plurality of coins are received. In the hopper 1, a coin feeding disc 2 is rotatably disposed on a base plate 3. The coin feeding disc 2 is rotated by the motor shaft 11 through the transmission 6, thereby a coin is fed. The number of the fed coins is counted by a counting microswitch. When the number of the fed coins is reached to a predetermined one, the electricity to the drive motor is immediately interrupted. Simultaneously, rotation of the motor shaft 11 is stopped by a brake mechanism 8 described below so that feeding of overabundant coins are prohibited.
Referring to FIG. 5, the brake mechanism 8 comprises a projection assembly and a brake engagement assembly. The projection assembly consists of a brake wheel 13 and a plurality of projections 14. The brake wheel 13 is made of synthetic resin and is attached to the motor shaft 11 so as to be rotated with the motor shaft 11. The projections 14 are integrally formed with the brake wheel 13, being equally apart from each other, on the perimeter thereof.
The brake engagement assembly comprises a claw piece 15 having a claw tip 18, a pivot pin 16, a spring 17, a release iron piece 19, a pivot axis 20, an attracted portion 21, a release piece 23, and a lower end 24 of the release iron piece. The claw tip 18 can be engaged with the projections 14. The pivot pin 16 is for use in pivotally supporting one end of the claw piece 15 to a stator 9 of the motor body 5. The claw piece 15 is always forced towards the projections 14 by the spring 17. The release iron piece 19 extends along an outer surface 22 of the stator 9. The pivot axis 20 is used for pivotally supporting one end of the release iron piece 19 to the stator 9. On the other end of the release iron piece 19, the attracted portion 21 is disposed which is attracted to the stator 9 when the motor body 5 is energized. The release piece 23 downwardly extends from the release iron piece 19 on its side facing to the attracted portion 21. The lower end 24 of the release iron piece contacts with a supporting shoulder 25 at the free end of the claw piece 15.
When a exciting coil 26 of the motor body 5 is energized, the attracted portion 21 is attracted to the outer surface 22 of the stator 9 due to magnetic attraction action of the stator 9. As a result, the release iron piece 19 is rotated in a clockwise direction around the pivot axis 20, thereby the lower end 24 of the release piece 23 pushes the supporting shoulder 25 of the claw piece 15 down against the spring force of the spring 17. The claw tip 18 of the claw piece 15 is out of engagement with one of the projection 14 of the brake wheel 13. Accordingly, the motor shaft 11 is maintained in a rotatable condition.
On the other hand, when the electricity to the exciting coil 26 of the motor body 5 is interrupted, no magnetic attraction action to the attracted portion 21 of the stator 9 is generated. As a consequence, the claw piece 15 is pushed towards the outer surface of the brake wheel 13 by the spring force of the spring 17. Accordingly, the claw tip 18 of the claw piece 15 engages with one of the projections 14 at a predetermined engagement position, thereby the motor 10 is prevented from rotating and the rotation of the motor shaft 11 is stopped. Simultaneously, the coin feeding disc 2 is also stopped from rotation and no coins are fed out.
Description will be made below regarding to a conventional coin feeding device.
A conventional coin feeding device generally comprises, as shown in FIGS. 4, 11, and ]2, a hollow cylindrical case 52 disposed at the lower end of the hopper 1, an outlet 53 provided at the lower end of the upper portion of surrounding surface of the hollow cylindrical case 52, a base plate 3, the coin feeding disc 2 disposed on the base plate 3, coin receiving holes 54, coin feeding arms 55, an outlet guiding member 56, and an outlet guiding pin 57. The hopper 1 defines a reception space for receiving a plurality of coins. The base plate 3 defines the bottom of the hollow cylindrical case 52. The coin feeding disc 2 is rotated by the motor shaft 11 of the drive motor due to its rotation. Each of the coin receiving holes 54 is penetrated through the coin feeding disc 2 and guides a coin A to the base plate 3. The coin feeding arms 55 are disposed between the coin feeding disc 2 and the base plate 3, being radially elongated to a circumference obtained by lacing an approximately center of the coin receiving holes 54. Each of the coin feeding arms 55 rotates accompanying with rotating coin feeding disc 2 and feeds the coin A to the outlet 53 by sliding thereof on the base plate 3. The outlet guiding member 56 is disposed between the coin feeding disc 2 and the base plate 3 at the downstream of the outlet 53 and guides the coin A delivered by the coin feeding arms 55 into the outlet 53. The outlet guiding pin 57 is provided on the base plate 3 and guides the coin A delivered by the coin feeding arms 55 to the outlet 53 in corporation with the outlet guiding member 56.
A scraper 59 has a plurality of coin feeding wings or fingers which is equal in number to the coin receiving holes 54 of the coin feeding disc 2. The scraper 59 rotates on the base plate 3 in synchronism with the coin feeding disc 2. Each of the coin feeding wings or fingers 58 feeds the coin A delivered by the outlet guiding member 56 and the outlet guiding pin 57 towards the outlet 53.
In the above-mentioned conventional brake mechanism, the claw tip of the claw piece is elastically forced to the brake wheel by means of the spring and is engaged with the projection to ensure braking. However, the claw tip is elastically pushed aside by the inertially rotated projections of the brake wheel due to the inertia force on braking. This results in incomplete braking for the coin feeding disc.
It is especially true with the increased inertia force on braking for the purpose of increasing the rotation speed of the drive motor, or with the worn claw and reduced spring force of the spring, because in such conditions the claw and the projections are readily pushed aside. Accordingly, it becomes difficult to completely stop the coin feeding disc at a predetermined engagement position and overabundant coins are thrown out.
On the other hand, in the above-mentioned conventional coin feeding device, the coin feeding disc is rotated in the reverse direction accompanying with the reversed rotation (in clockwise direction) of the motor shaft caused by the reversed rotation of the motor. In this event, the coin delivered from the coin receiving hole to the base plate collides with the outlet guiding member and the outlet guiding pin. Accordingly, the coin is caught between the outlet guiding member with the outlet guiding pin and the coin feeding arms and is fixed therebetween. This causes interruption of reversed rotation of the coin feeding disc, and in turn, that of the motor shaft.
It is therefore a principle object of the present invention to provide a drive motor of which motor shaft can be completely stopped even when the inertia force after braking in increased, or when the claw is worn and the spring force of the spring is reduced after long use, with respect to the above mentioned problem caused to the drive motor.
It is another object of the present invention to provide a coin feeding device which allows reversed rotation of the coin feeding disc and the motor shaft without causing the coin being caught between the outlet guiding member with the outlet guiding pin and the coin feeding arms and fixed therebetween, with respect to the above mentioned problem caused in the coin feeding device.
Other objects and advantages of the present invention will be clear as the description proceeds.